Monthly Archives: September 2009

Stir-on-LAN

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I got Wake-on-LAN almost working on my desktop computer. It took some trial and error, but here are the essential steps:

  • I configured my Gigabyte S-series GA-MA790FX-DS5 motherboard BIOS to have PME Event set to enabled; this enables wake-on-LAN which means, apparently, that the NIC still receives a little bit of power in order to check for the Magic Packet. I also tweaked the ACPI configuration by setting the ACPI Suspend Type to be S3(STR), so that when I do a suspend (rather than hibernate or power-off), only RAM gets power and not the CPU.

  • I changed /etc/rc./init.d/halt so that it ends with:

    # Wakeup-on-LAN

/usr/sbin/ethtool -s eth0 wol g
sleep 5 # one source claims this matters

exec $command $HALTARGS

  • I created /etc/pm/sleep.d/99network:

    # Restart the network interfaces after suspending
# Author: Victor Chudnovsky (victor dot chudnovsky at g m a i l  dot c o m)

case "$1" in
    thaw|resume)
        service network restart
        ;;
    suspend|hibernate)
        /usr/sbin/ethtool -s eth0 wol g
    sleep 5 # one source claims this matters
        ;;
    *)
        ;;
esac

exit $?

  • To allow waking up my desktop from the outside, I made sure my router allows WOL packets to reach the machine. One can do this either by setting the machine to be the DMZ server or by explictly configuring these packets to be routed through (typically on port 9)

  • Possibly unnecessary but it can’t hurt: Disabled the standard r8169 driver and instead installed the official r8168 RealTek driver for my onboard Realtek 8111B ethernet chip. I followed the directionsin the README, which essentially amount to the steps here.

  • Possibly unnecessary: I created /etc/pm/config.d/config with contents:

    SUSPEND_MODULES="r8168"

That was enough to enable suspend-to-LAN. To actually wake the computer, one needs a client that can send the Magic Packet to the wakeable machine. These clients thus need the IP address of the machine (or a broadcast address) and the MAC address of the NIC that is a wol-able.

  • I got an Android app for my phone, aWOL that allows multiple profies for various machines that can be woken up remotely.

  • I installed ether-wake and wol clients on various computers from which I want to wake up my desktop.

This set-up seems to work pretty well. There are some occasional issues I’m encountering that I’m still trying to debug:

  • Rarely, I’ve noticed that if I suspend or hibernate and resume too many times too quickly, these operations start failing with a Device or resource busy message in /var/log/pm-suspend/log, but if I wait for a while and try again, it starts working.

  • The remaining problem is this: if I’m powered off for too long, the card does not respond to the Magic Packet. This defeats the whole purpose of this feature, obviously, so I’m trying to figure out under what conditions this happens. I found this problem mentioned elsewhere, but no solution as of yet. I asked Gigabyte customer support, but have not heard back from them yet.

For more information, refer to the Xlife wol guide or the Wake-on-LAN mini-HOWTO .

Snow Leopard, uncrashed

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Knox has been having a bunch of problems upgrading his Mac to Snow Leopard. After much digging today, he discovered in the system log that startd was complaining about having to throttle cupsd from too-frequent respawning due to recurring crashes. The fix, which is described here, is to revert /etc/cups/cupsd.conf to /etc/cups/cupsd.conf.default.

How annoying that a critical service would crash on a misconfigured settings file! That is non-defensive software engineering. And shame on the upgrade process that mangled the configuration file!

Interestingly, Knox reports that applications that were querying for the default printer were also crashing (OmniGraffle, Photoshop). I wonder whether they all happen to be programmed in a brittle fashion, or whether the system somehow makes them crash when CUPS crashes. Both of those seem unlikely.

The Power of Now

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One of my pursuits these days is the cultivation of mindfulness. Life is rich and helter-skelter. Only by living in each fleeting now, it seems, is there hope of appreciating a journey that is already accelerating to its eventual conclusion. Existential crisis? Perhaps, but fairly benign as those go.

It was with some anticipation, then, that I picked up Eckhart Tolle’s acclaimed The Power of Now: A Guide To Spiritual Enlightenment. I tried to slog through it, really I did, but there was too little psychological wheat to be salvaged from all the pseudo-scientific chaff that pervades the book.

What am I talking about? Vague references to “vibrational frequencies” that, when elevated by mindfulness, allow one to not be affected by “negativity.” Ok, I can bend over backwards and internally translate this as a metaphor of psychological states one can reach and imagery that can take one there. But then he also rails against “thought” and “mind” trapping us and being the obstacles from which we must seek liberation. I don’t buy it; it is ego and anxiety and fixation on the past and future that bind us, and careful thought can often be a liberating tool. We probably do need to take a break from being analytical all the time—but the blanket statment that rationality is an obstacle to enlightenment hardly follows from that in my book, and that is a distinctinion Tolle makes hapharzadly at best. Sloppy language, in fact, pervades the book: Tolle’s statements that past and present don’t really exist certainly are phrased to explicitly mean that physical time is illusory, but then he inconsistently backtracks from this solipsism by occasionally making reasonable distinctions between “wall” and “psychological” time.

What else? The kicker is his use of pseudoscientific jargon in ways that are clearly not meant to be taken metaphorically (or if they are, they constitute a reckless indulgence in the fallacy of equivocation): “As there is more consciousness in the body, its molecular structure actually becomes less dense.” As a scientist, engineer, and humanist, I cannot just let that slide.

What is left after ignoring, sighing, or eye-rolling through the pseudo-science is nothing that I haven’t encountered elsewhere: One must get beyond ego. While there’s no need to be passive, one must accept what is. Wherever you are, be there. I was hoping perhaps there would be some concrete practical guides to mindfulness practice, but no. It’s just your standard breathing practice and everyday presence, and more description of what mindfulness is rather than how to get it.

I’ve found better mindfulness books that are practical, focused, and secular. Jon Kabat Zinn’s Wherever You Go, There You Are is one; Mindfulness in Plain English is another. They seem mostly (but certainly not exclusively) focused on sitting practice, for which I struggle and fail to set aside time. I seem to be leaning more towards “everyday mindfulness,” re-focusing on the wide-eyed wonder and joy that I felt not that long ago when everyday life was (or just seemed) less hectic.

Portland to Astoria Century

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This weekend a friend invited us to ride a century from Portland to Astoria with a bunch of his pals. It was a fun ride through largely new-to-me territory. Not terribly hard, though tiring in that way that centuries tend to be. We had frequent stops to re-group, a sag wagon that refilled our waters, and rides back to Portland for us and our bikes. It was pretty sweet, except for the chafing my new bike shorts caused me.

It was interesting biking with a new crowd; the ride felt somewhere in between our usual weekend bike trips and the large organized rides we’ve been doing this summer. Folks were relaxed and looking out for everyone in the group, but certainly more hard-core into the cycling world than Knox or I. They seemed more interested in organized events like triathlons than the bike-touring we do, so I appreciated getting a different perspective on the sport.

Before we left Portland, we were underwhelmed at the St. Honoré Boulangerie, delighted in the visual and olfactory pleasures at the rose garden, and visited the well-stocked yet slightly pricey River City Bicycles.


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Why Choose This Book?

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Starting from Darwin and Turing, Read Montague’s Why Choose This Book? relates recent research on how minds make decisions. The critical element is a valuation mechanism that can assign weights to various alternatives, and do so cheaply. Why, indeed, does a computer heat up so much while our own more complex brains are barely warm?

The book deals with an interesting topic, but I felt that it was a slow read. I would have liked the chapters to feel more coherent and pull this lay person along in a more systematic and fast-paced manner.